1 files changed, 114 insertions, 0 deletions
diff --git a/src/cmd/gofix/netdial.go b/src/cmd/gofix/netdial.go
new file mode 100644
index 000000000..afa98953b
--- /dev/null
+++ b/src/cmd/gofix/netdial.go
@@ -0,0 +1,114 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"go/ast"
+)
+
+var netdialFix = fix{
+	"netdial",
+	netdial,
+	`Adapt 3-argument calls of net.Dial to use 2-argument form.
+
+http://codereview.appspot.com/4244055
+`,
+}
+
+var tlsdialFix = fix{
+	"tlsdial",
+	tlsdial,
+	`Adapt 4-argument calls of tls.Dial to use 3-argument form.
+
+http://codereview.appspot.com/4244055
+`,
+}
+
+var netlookupFix = fix{
+	"netlookup",
+	netlookup,
+	`Adapt 3-result calls to net.LookupHost to use 2-result form.
+
+http://codereview.appspot.com/4244055
+`,
+}
+
+func init() {
+	register(netdialFix)
+	register(tlsdialFix)
+	register(netlookupFix)
+}
+
+func netdial(f *ast.File) bool {
+	if !imports(f, "net") {
+		return false
+	}
+
+	fixed := false
+	walk(f, func(n interface{}) {
+		call, ok := n.(*ast.CallExpr)
+		if !ok || !isPkgDot(call.Fun, "net", "Dial") || len(call.Args) != 3 {
+			return
+		}
+		// net.Dial(a, "", b) -> net.Dial(a, b)
+		if !isEmptyString(call.Args[1]) {
+			warn(call.Pos(), "call to net.Dial with non-empty second argument")
+			return
+		}
+		call.Args[1] = call.Args[2]
+		call.Args = call.Args[:2]
+		fixed = true
+	})
+	return fixed
+}
+
+func tlsdial(f *ast.File) bool {
+	if !imports(f, "crypto/tls") {
+		return false
+	}
+
+	fixed := false
+	walk(f, func(n interface{}) {
+		call, ok := n.(*ast.CallExpr)
+		if !ok || !isPkgDot(call.Fun, "tls", "Dial") || len(call.Args) != 4 {
+			return
+		}
+		// tls.Dial(a, "", b, c) -> tls.Dial(a, b, c)
+		if !isEmptyString(call.Args[1]) {
+			warn(call.Pos(), "call to tls.Dial with non-empty second argument")
+			return
+		}
+		call.Args[1] = call.Args[2]
+		call.Args[2] = call.Args[3]
+		call.Args = call.Args[:3]
+		fixed = true
+	})
+	return fixed
+}
+
+func netlookup(f *ast.File) bool {
+	if !imports(f, "net") {
+		return false
+	}
+
+	fixed := false
+	walk(f, func(n interface{}) {
+		as, ok := n.(*ast.AssignStmt)
+		if !ok || len(as.Lhs) != 3 || len(as.Rhs) != 1 {
+			return
+		}
+		call, ok := as.Rhs[0].(*ast.CallExpr)
+		if !ok || !isPkgDot(call.Fun, "net", "LookupHost") {
+			return
+		}
+		if !isBlank(as.Lhs[2]) {
+			warn(as.Pos(), "call to net.LookupHost expecting cname; use net.LookupCNAME")
+			return
+		}
+		as.Lhs = as.Lhs[:2]
+		fixed = true
+	})
+	return fixed
+}